Dielectric and conductivity studies of the hydration mechanisms in plant seeds

Konsta, AA; Pissis, P; Kanapitsas, A; Ratkovic, S

dc.contributor.author	Konsta, AA	en
dc.contributor.author	Pissis, P	en
dc.contributor.author	Kanapitsas, A	en
dc.contributor.author	Ratkovic, S	en
dc.date.accessioned	2014-03-01T01:11:53Z
dc.date.available	2014-03-01T01:11:53Z
dc.date.issued	1996	en
dc.identifier.issn	0006-3495	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/11845
dc.subject.classification	Biophysics	en
dc.subject.other	water	en
dc.subject.other	article	en
dc.subject.other	conductance	en
dc.subject.other	crystallization	en
dc.subject.other	depolarization	en
dc.subject.other	diffusion coefficient	en
dc.subject.other	energy	en
dc.subject.other	hydration	en
dc.subject.other	moisture	en
dc.subject.other	nonhuman	en
dc.subject.other	plant seed	en
dc.subject.other	spectroscopy	en
dc.subject.other	temperature	en
dc.subject.other	Biophysics	en
dc.subject.other	Electric Conductivity	en
dc.subject.other	Electrochemistry	en
dc.subject.other	Seeds	en
dc.subject.other	Temperature	en
dc.subject.other	Thermodynamics	en
dc.subject.other	Water	en
dc.title	Dielectric and conductivity studies of the hydration mechanisms in plant seeds	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0006-3495(96)79710-2	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0006-3495(96)79710-2	en
heal.language	English	en
heal.publicationDate	1996	en
heal.abstract	The hydration mechanism of various plant seeds has been investigated by a) sorption-desorption isotherms, b) ac-dielectric spectroscopy in the 10 Hz to 1 GHz frequency range and the -80 to + 40 degrees C temperature range, and c) thermally stimulated depolarization current techniques in the -170 to +23 degrees C temperature range. Seeds of different chemical composition were studied at water contents varying between 0 and 40% w/w (dry weight basis). Our experimental results permitted us to determine i) the diffusion constant of water in the samples, found to be between 1.4 x 10(-11) and 3.7 x 10-(11) m(2)/s; ii) a critical water content corresponding to the completion of the primary hydration layer, which is in the range 0.11-0.17 w/w, depending on the seed nature; and iii) the activation energy of the main relaxation mechanism, found to be equal to 0.54 +/- 0.05 eV. Moreover, they make it possible to investigate the dependence of various parameters (conductivity, molecular mobility, plasticizing effect of water) on the water content of the sample, to follow the crystallization of water in the seeds as a function of temperature and confirm that it is not a reversible process, to study the dehydration process as a function of temperature and time, and to propose an alternative technique for the determination of the moisture content in seeds.	en
heal.publisher	BIOPHYSICAL SOCIETY	en
heal.journalName	Biophysical Journal	en
dc.identifier.doi	10.1016/S0006-3495(96)79710-2	en
dc.identifier.isi	ISI:A1996UB81700038	en
dc.identifier.volume	70	en
dc.identifier.issue	3	en
dc.identifier.spage	1485	en
dc.identifier.epage	1493	en